Abstract:

Provided are a ventilation hooded microwave oven and a cooling system for
the ventilation hooded microwave oven. In the ventilation hooded
microwave oven, a pull-up door is provided, and various components of a
cavity assembly, the pull-up door, and a door handle can be cooled by
airflows induced by a cooling fan assembly. Therefore, outside areas of
the ventilation hooded microwave oven can be efficiently used, and the
ventilation hooded microwave oven can be reliably prevented from
overheating.

Claims:

1. A ventilation hooded microwave oven having a cavity assembly and a
door, the cavity assembly having a cooking chamber for cooking food and
an electric component room in which a plurality of electric components is
disposed, the door being rotatably attached to the cavity assembly such
that a lower end portion of the door is rotatable upward or downward
about an upper end portion of the door to open or close the cooking
chamber, the ventilation hooded microwave oven being characterized in
that the ventilation hooded microwave oven comprises:a cooling fan
assembly generating power to create flows of air into and out of the
cavity assembly;a vent grill at a front side of the cavity assembly to
guide air into and out of the cavity assembly; andan interference
preventing portion at a rear side of the door to prevent an interference
between the door and the vent grill when the door is rotated to
selectively close and open the cooking chamber.

2. The ventilation hooded microwave oven according to claim 1, wherein the
cooling fan assembly is disposed at a front upper portion of the cavity
assembly in front of the electric component room so as to place a suction
portion of the cooling fan assembly close to an air inlet portion of the
cavity assembly, and to direct air discharged through a discharge portion
of the cooling fan assembly toward the electric component room.

3. A ventilation hooded microwave oven having a cavity assembly and a
door, the cavity assembly having a cooking chamber for cooking food and
an electric component room in which a plurality of electric components is
disposed, the door having a door handle at a front side and being
rotatably attached to the cavity assembly such that a lower end portion
of the door is rotatable upward or downward about an upper end portion of
the door to open or close the cooking chamber, the ventilation hooded
microwave oven being characterized in that the ventilation hooded
microwave oven comprises:a cooling fan assembly generating power so as to
force air to flow into and out of the door and then into and out of the
cavity assembly;a vent grill at a front side of the cavity assembly so as
to guide air flowing from the door to the cavity assembly and to guide
air discharged from the cavity assembly; andan interference preventing
portion at a rear side of the door so as to prevent an interference
between the door and the vent grill when the door is rotated to
selectively close and open the cooking chamber.

4. The ventilation hooded microwave oven according to claim 3, wherein the
cooling fan assembly is disposed at a front upper portion of the cavity
assembly in front of the electric component room so as to place a suction
portion of the cooling fan assembly close to an air inlet portion of the
cavity assembly through which air flows from the door to the cavity
assembly, and to direct air discharged through a discharge portion of the
cooling fan assembly toward the electric component room.

5. The ventilation hooded microwave oven according to claim 3, further
comprising a first air duct forming a passage, wherein after the electric
components of the electric component room are cooled by air introduced
through a front-side inlet portion of the cavity assembly by the cooling
fan assembly, the air is guided from the electric component room to the
cooking chamber through the passage of the first duct.

6. The ventilation hooded microwave oven according to claim 5, further
comprising a second air duct forming a passage so as to allow air
circulated in the cooking chamber and discharged from the cooking chamber
to be discharged through a frontside outlet portion of the cavity
assembly.

7. The ventilation hooded microwave oven according to claim 3, wherein air
intruded into the door through an inlet hole of the door and circulated
in the door to cool the door is discharged through an outlet hole of the
door, and then the air is introduced into the cavity assembly through the
inlet portion of the cavity assembly.

8. The ventilation hooded microwave oven according to claim 7, wherein the
outlet hole is disposed at a side of the interference preventing portion,
and the vent grill comprises a suction passage communicating with the
outlet hole when the cooking chamber is closed by the door.

9. The ventilation hooded microwave oven according to claim 7, wherein the
inlet hole is disposed at a side of an upper end portion of the door
farthest from the outlet hole.

10. The ventilation hooded microwave oven according to claim 3, wherein
the interference preventing portion is covered with a front member
forming a front exterior of the door.

11. The cooling system according to claim 10, wherein the front member is
a front glass.

12. The ventilation hooded microwave oven according to claim 3, further
comprising a lead wire cap detachably inserted in the vent grill with a
gap therebetween.

13. The ventilation hooded microwave oven according to claim 12, wherein
air discharged from the cavity assembly is guide along a discharge
passage disposed in the lead wire cap, and a lead wire is laid from the
cavity assembly into the door through a wire accommodation gap between
the vent grill and the lead wire cap.

14. The ventilation hooded microwave oven according to claim 10, wherein a
lead wire is laid from the wire accommodation gap into the door through a
lead wire opening located at a side of the vent grill.

15. The ventilation hooded microwave oven according to claim 14, wherein
the lead wire laid into the door is connected to a display unit
configured to receive operational commands and display information about
operation of the ventilation hooded microwave oven.

16. The ventilation hooded microwave oven according to claim 3, further
comprising an air guide at a top portion of the cavity assembly to
separate the electric component room from a vent passage.

17. The ventilation hooded microwave oven according to claim 16, wherein
the air guide separates the electric component room and the vent passage
in a manner such that the electric component room becomes wider toward
the front side of the cavity assembly, and the vent passage becomes
narrower toward the front side of the cavity assembly.

18. The ventilation hooded microwave oven according to claim 16, wherein
the air guide is formed of a metal, and a front portion of the air guide
is sloped toward the vent passage.

19. The ventilation hooded microwave oven according to claim 3, wherein an
opening is disposed at a bottom surface of the electric component room to
guide air circulated in the electric component room to cool the electric
components into the cooking chamber when the cooling fan assembly
operates.

20. An airflow system for a ventilation hooded microwave oven having a
cavity assembly in which a cooking chamber is disposed and a door
configured to selectively open and close the cooking chamber, the airflow
system comprising:a cooling fan assembly configured to force air to flow
into the door and the cavity assembly and then out of the cavity assembly
after the air cools electric components and is circulated in the cooling
chamber;a vent fan assembly configured to introduce fumes from food
cooked on a cooker disposed under the cavity assembly into the cavity
assembly and discharge the fumes from the cavity assembly; anda vent
grill through which flows of air and fumes induced by the cooling fan
assembly and the vent fan assembly are discharged from the cavity
assembly.

21-36. (canceled)

Description:

TECHNICAL FIELD

[0001]The present disclosure relates to a ventilation hooded microwave
oven, and more particularly, to a ventilation hooded microwave oven
including a pull-up door for opening and closing a cooking chamber, and a
cooling system for the ventilation hooded microwave oven.

BACKGROUND ART

[0002]Microwave ovens are household appliances used to cook foods using
microwaves and heat. Generally, a microwave oven includes a cavity
assembly and a door. The cavity assembly includes a cooking chamber, and
one side of the door is rotatably fixed to the cavity assembly. Thus, the
cooking chamber can be opened or closed by pulling or pushing the other
side of the door.

[0003]Some microwave ovens (ventilation hooded microwave ovens) installed
in furniture are designed to function as a hood for discharging smoke and
fumes generated while food is cooked using a cooker disposed under the
microwave oven. A display unit can be installed in a door of a microwave
oven to receive commands from a user and display information about the
operation of the microwave oven.

[0004]However, such microwave ovens of the related art have disadvantages
as follows.

[0005]Since the cooking chamber is opened or closed by rotating the other
side of the door forward or backward, it is inconvenient to place
articles at both sides of the microwave oven when the door pulled for
opening the cooking chamber.

[0006]Furthermore, the door is movable after it is pulled for opening the
cooking chamber. Therefore, it is inconvenient to place food into the
cooking chamber and take the food out of the cooking chamber owing to the
movable opened door.

[0007]In the case of the ventilation hooded microwave oven installed in
furniture, a hinge assembly used to attach a door to a cavity assembly is
disposed within the furniture. Therefore, the whole microwave oven should
be first detached from the furniture to separate the door from the cavity
assembly.

[0008]Furthermore, due to a passage formed in the cavity assembly of the
ventilation hooded microwave oven for discharging smoke and fumes, spaces
for other electric components are insufficient.

[0009]Moreover, the ventilation hooded microwave oven should be first
detached from the furniture when repairing or replacing electric
components or other components of the ventilation hooded microwave oven.

[0010]Meanwhile, a door of a microwave oven can be overheated while food
is cooked in a cooking chamber. Therefore, a user can be injured when
holding the door, and a display unit installed in the door can be damaged
by heat.

DISCLOSURE OF INVENTION

Technical Problem

[0011]Embodiments provide a door for a ventilation hooded microwave oven,
the door being designed so that surrounding spaces of the door can be
efficiently used.

[0012]Embodiments also provide a door for a ventilation hooded microwave
oven, the door being designed so that food can be placed into and taken
out of the ventilation hooded microwave oven more easily.

[0013]Embodiments also provide a door for a ventilation hooded microwave
oven, the door being designed so that a sufficiently large space can be
allocated for an electric component room.

[0014]Embodiments also provide a door for a ventilation hooded microwave
oven, the door being designed so that a display unit disposed in the door
can be reliably protected.

[0015]Embodiments also provide a door for a ventilation hooded microwave
oven, the door being designed so that the possibility of accidents can be
reduced.

Technical Solution

[0016]In one embodiment, there is provided a ventilation hooded microwave
oven having a cavity assembly and a door, the cavity assembly having a
cooking chamber for cooking food and an electric component room in which
a plurality of electric components is disposed, the door being rotatably
attached to the cavity assembly such that a lower end portion of the door
is rotatable upward or downward about an upper end portion of the door to
open or close the cooking chamber, the ventilation hooded microwave oven
being characterized in that the ventilation hooded microwave oven
includes: a cooling fan assembly generating power to create flows of air
into and out of the cavity assembly; a vent grill at a front side of the
cavity assembly to guide air into and out of the cavity assembly; and an
interference preventing portion at a rear side of the door to prevent an
interference between the door and the vent grill when the door is rotated
to selectively close and open the cooking chamber.

[0017]In another embodiment, there is provided a ventilation hooded
microwave oven having a cavity assembly and a door, the cavity assembly
having a cooking chamber for cooking food and an electric component room
in which a plurality of electric components is disposed, the door having
a door handle at a front side and being rotatably attached to the cavity
assembly such that a lower end portion of the door is rotatable upward or
downward about an upper end portion of the door to open or close the
cooking chamber, the ventilation hooded microwave oven being
characterized in that the ventilation hooded microwave oven includes: a
cooling fan assembly generating power so as to force air to flow into and
out of the door and then into and out of the cavity assembly; a vent
grill at a front side of the cavity assembly so as to guide air flowing
from the door to the cavity assembly and to guide air discharged from the
cavity assembly; and an interference preventing portion at a rear side of
the door so as to prevent an interference between the door and the vent
grill when the door is rotated to selectively close and open the cooking
chamber.

[0018]In a further embodiment, there is provided an airflow system for a
ventilation hooded microwave oven having a cavity assembly in which a
cooking chamber is disposed and a door configured to selectively open and
close the cooking chamber, the airflow system including: a cooling fan
assembly configured to force air to flow into the door and the cavity
assembly and then out of the cavity assembly after the air cools electric
components and is circulated in the cooling chamber; a vent fan assembly
configured to introduce fumes from food cooked on a cooker disposed under
the cavity assembly into the cavity assembly and discharge the fumes from
the cavity assembly; and a vent grill through which flows of air and
fumes induced by the cooling fan assembly and the vent fan assembly are
discharged from the cavity assembly.

Advantageous Effects

[0019]The present disclosure provides efficient use of surrounding spaces
of a microwave oven, easy loading and unloading of food to and from a
cooking chamber of the microwave oven, each detachment of a door of the
microwave oven, a sufficiently large room for an electric component room
of the microwave oven, easy repair and replacement of components of the
microwave oven, reliable protection for a display unit of the door, and
reliable prevention of accidents.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020]FIG. 1 is an exploded perspective view illustrating a ventilation
hooded microwave oven according to a first embodiment.

[0021]FIG. 2 is a perspective view illustrating an assembled state of the
ventilation hooded microwave oven according to the first embodiment.

[0022]FIG. 3 is a vertical sectional view illustrating a latch board of
the ventilation hooded microwave oven according to the first embodiment.

[0023]FIG. 4 is a perspective view illustrating a door support bracket of
the ventilation hooded microwave oven according to the first embodiment.

[0024]FIG. 5 is a perspective view illustrating an air barrier of the
ventilation hooded microwave oven according to the first embodiment.

[0025]FIG. 6 is a perspective view illustrating a vent grill and a lead
wire cap of the ventilation hooded microwave oven according to the first
embodiment.

[0026]FIG. 7 is a vertical sectional view illustrating an assembled state
of the vent grill and the lead wire cap according to the first
embodiment.

[0027]FIG. 8 is an exploded perspective view illustrating a door of the
ventilation hooded microwave oven according to the first embodiment.

[0028]FIG. 9 is a front view illustrating the door according to the first
embodiment.

[0029]FIGS. 10 to 12 are partial perspective views for explaining
procedures for attaching the door to a cavity assembly of the ventilation
hooded microwave oven according to the first embodiment.

[0030]FIGS. 13 to 17 are views for explaining how the door of the
ventilation hooded microwave oven is opened according to the first
embodiment.

[0031]FIGS. 18 to 20 are views illustrating exemplary flows of air in the
ventilation hooded microwave oven according to the first embodiment.

[0032]FIG. 21 is a side view illustrating a door support device for
supporting a door of a ventilation hooded microwave oven according to a
second embodiment.

[0033]FIG. 22 is a partial perspective view illustrating a door support
device of a ventilation hooded microwave oven according to a third
embodiment.

[0034]FIG. 23 is a perspective view illustrating a cam hinge of a
ventilation hooded microwave oven according to a fourth embodiment.

[0035]FIGS. 24 and 25 are perspective views illustrating how the cam hinge
operates when a door of the ventilation hooded microwave oven is opened
and closed according to the fourth embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION

[0036]A ventilation hooded microwave oven and a cooling system for the
ventilation hooded microwave oven will now be described in detail with
reference to the accompanying drawings according to a first embodiment.

[0037]FIG. 1 is an exploded perspective view illustrating a ventilation
hooded microwave oven according to a first embodiment, and FIG. 2 is a
perspective view illustrating an assembled state of the ventilation
hooded microwave oven according to the first embodiment. FIG. 3 is a
vertical sectional view illustrating a latch board of the ventilation
hooded microwave oven according to the first embodiment, and FIG. 4 is a
perspective view illustrating a door support bracket of the ventilation
hooded microwave oven according to the first embodiment. FIG. 5 is a
perspective view illustrating an air barrier of the ventilation hooded
microwave oven according to the first embodiment, and FIG. 6 is a
perspective view illustrating a vent grill and a lead wire cap of the
ventilation hooded microwave oven according to the first embodiment. FIG.
7 is a vertical sectional view illustrating an assembled state of the
vent grill and the lead wire cap according to the first embodiment, and
FIG. 8 is an exploded perspective view illustrating a door of the
ventilation hooded microwave oven according to the first embodiment. FIG.
9 is a front view illustrating the door according to the first
embodiment.

[0038]Referring to FIGS. 1 to 9, a cooking chamber 111 is formed in a
cavity assembly 100 of the ventilation hooded microwave oven
(hereinafter, also referred to as a microwave oven). The cooking chamber
111 is a room for cooking food and is selectively opened and closed by a
door 200.

[0039]A plurality of inlet holes 113 (refer to FIG. 20) is formed in a
side portion of the cooking chamber 111, and a plurality of outlet holes
115 (refer to FIG. 20) is formed in the topside of the cooking chamber
111. The inlet holes 113 are formed in the right side of the cooking
chamber 111 when viewed in FIG. 20 for introducing air into the cooking
chamber 111. When viewed in FIG. 20, the outlet holes 115 are formed in a
right edge portion of the topside of the cooking chamber 111 away from
the inlet holes 113 for discharging air from the cooking chamber 111.

[0040]An inlet portion 121 and an outlet portion are formed in a front
upper side of the cavity assembly 100. The inlet portion 121 is formed in
one side of the front upper side of the cavity assembly 100 (the right
side of the front upper side of the cavity assembly 100 when viewed in
FIG. 1). The inlet portion 121 allows air used to cool the door 200 to be
introduced into the cavity assembly 100. The outlet portion includes a
first outlet 123 and a second outlet 124. The first outlet 123 is formed
in the other side of the front upper side of the cavity assembly 100
opposite to the inlet portion 121. That is, the first outlet 123 is
formed in the left side of the front upper side of the cavity assembly
100 when viewed in FIG. 1. The second outlet 124 is formed in a center
portion of the front upper side of the cavity assembly 100 between the
inlet portion 121 and the first outlet 123. Air is discharged from the
cavity assembly 100 through the first outlet 123. Smoke and fumes, which
are generated from food cooked on a cooker disposed under the microwave
oven and introduced into the cavity assembly 100, are discharged from the
cavity assembly 100 through the second outlet 124 when a vent fan
assembly 166 (described later) operates.

[0041]A terminal opening 125 is formed in the front upper side of the
cavity assembly 100 between the first outlet 123 and the second outlet
124. A terminal housing (not shown) is coupled to the cavity assembly 100
through the terminal opening 125. The terminal housing protrudes forward
from the cavity assembly 100. A terminal (not shown) may be connected to
the terminal housing to transmit power and various signals to a display
unit 260 of the door 200.

[0042]A service opening 127 is formed in a portion of the front upper side
of the cavity assembly 100 opposite to the outlet portion. That is, the
service opening 127 is formed at the right of the inlet portion 121. A
capacity 155 (described later) can be replaced through the service
opening 127. Thus, the size and shape of the service opening 127 are
determined based on the size of the capacity 155. The

[0043]service opening 127 can be selectively opened and closed by an
opening/closing bracket 129. The opening/closing bracket 129, that is the
service opening 127, is exposed when the door 200 rotates to open the
cooking chamber 111. In other words, the service opening 127 is formed in
a portion of the cavity assembly 100 that makes contact with a rear
surface of the door 200 when the cooking chamber 111 is closed by the
door 200.

[0044]Door support brackets 131 are disposed in both sides of the front
surface of the cavity assembly 100, and a detailed view of the door
support bracket 131 is shown in FIG. 4. The door support brackets 131
support the door 200 and allow rotation of the door 200. Each of the door
support brackets 131 has a L-shaped cross section and is vertically
elongated. When assembled, front surfaces of the door support brackets
131 make tight contact with both sides of a front inner surface of the
cavity assembly 100. A fixing rib 132 is formed on a rear surface of the
door support bracket 131. When assembled, the fixing rib 132 is fixed to
a top surface of the cavity assembly 100. The door support bracket 131
includes a hinge bracket 133 and a hinge cover 137.

[0045]The hinge bracket 133 is formed on a front upper portion of the door
support bracket 131. When assembled, the hinge bracket 133 protrudes
forward from a lateral side of the front surface of the cavity assembly
100. The hinge bracket 133 is U-shaped with an opened top and protrudes
forward from the lateral side of the front surface of the cavity assembly
100 when the door support bracket 131 is coupled to the cavity assembly
100. Here, the protruded length of the hinge bracket 133 from the cavity
assembly 100 is adjusted such that a predetermined portion (i.e., a
coupling hole 136) of the hinge bracket 133 is exposed to the outside
when the microwave oven is installed in furniture above a cooker.

[0046]The hinge bracket 133 includes hinge grooves 134 in both sides. The
hinge grooves 134 are vertically formed in top surfaces of both sides of
the hinge bracket 133. The hinge grooves 134 receive a hinge pin 228
(described later). The hinge pin 228 can be inserted into the hinge
grooves 134 from the top of the hinge bracket 133.

[0047]A coupling flange 135 is disposed at the hinge bracket 133. The
coupling flange 135 can be formed by cutting a horizontally elongated
bottom portion of the hinge bracket 133 into a rectangular shape and
bending the cut portion into an L-shape. The coupling hole 136 is formed
in a top surface of the coupling flange 135 for fixing the hinge cover
137 to the hinge bracket 133. The coupling hole 136 formed in the top
surface of the coupling flange 135 is exposed to the outside when the
microwave oven is installed in furniture.

[0048]The hinge cover 137 is disposed at a top portion of the door support
bracket 131 above the hinge bracket 133. When the door support bracket
131 is coupled to the cavity assembly 100, the hinge cover 137 protrudes
forward through a lateral side of a front upper portion of the cavity
assembly 100. The hinge cover 137 is U-shaped and has a downwardly opened
side. The hinge cover 137 is rotatable on its rear edge. Thus, when the
hinge pin 228 is inserted into the hinge grooves 134, the hinge cover 137
can be rotated down to securely hold the hinge pin 228 in the hinge
grooves 134.

[0049]For this, hinge pin openings 138 are formed in both lower sides of
the hinge cover 137. The hinge pin openings 138 can be formed by
partially cutting both lower sides of the hinge cover 137 into a
downwardly sloped shape. When the hinge cover 137 is rotated down, the
hinge pin 228 inserted in the hinge grooves 134 is inserted into the
hinge pin openings 138.

[0050]After the hinge cover 137 is rotated down (i.e., when the hinge pin
228 is inserted into the hinge pin openings 138), the hinge bracket 133
is disposed inside the hinge cover 137. In this state, both upper sides
of the hinge bracket 133 make tight contact with inner surfaces of the
hinge cover 137.

[0051]A penetration hole 139 is formed through a top surface of the hinge
cover 137. After rotating down the hinge cover 137 to hold the hinge pin
228 in the hinge grooves 134 of the hinge bracket 133, a screw (S) (refer
to FIG. 12) can be fixed to the coupling hole 136 of the hinge bracket
133 through the penetration hole 139 of the hinge cover 137 to prevent
movement of the hinge cover 137. For this, when the hinge cover 137 is
rotated down (i.e., when the hinge cover 137 holds the hinge pin 228 in
the hinge grooves 134), the penetration hole 139 of the hinge cover 137
is aligned with the coupling hole 136 of the hinge bracket 133. Thus, the
penetration hole 139 of the hinge cover 137 as well as the coupling hole
136 of the hinge bracket 133 is exposed to the outside when the microwave
oven is installed in furniture.

[0052]Spring fixing portions 141 protrude forward from both front sides of
the cavity assembly 100. The spring fixing portions 141 are located under
the hinge covers 137 when the door support brackets 131 are coupled to
the cavity assembly 100. Gas springs 300 (refer to FIG. 1) are fixed to
the spring fixing portions 141. The spring fixing portions 141 are fixed
to the door support brackets 131 disposed in the cavity assembly 100 and
protrude forward from both front sides of the cavity assembly 100 by a
predetermined length. Each of the spring fixing portions 141 includes a
horizontal spring fixing protrusion 143.

[0053]Latch slots 145 are disposed at both sides of a lower front surface
of the cavity assembly 100. The latch slots 145 can be formed by
partially cutting out both sides of the lower front surface of the cavity
assembly 100 into a horizontally elongated rectangular shape. The latch
slots 145 receive latch protrusions 281 (refer to FIG. 8).

[0054]A latch board 146 is disposed in the cavity assembly 100 at a
position corresponding to the latch slot 145, and a detailed view of the
latch board 146 is shown in FIG. 3. The latch board 146 includes an
actuation lever 147, a pair of latch switches 148, and a pair of torsion
springs 149. When the door 200 is closed, the actuation lever 147 locks
the latch protrusion 281 inserted in the latch slot 145 to hold the door
200 in closed position, thereby preventing undesired opening of the
cooking chamber 111. When the actuation lever 147 is moved backward along
an upwardly sloped path by the latch protrusion 281 inserted into the
latch slot 145, the latch switches 148 are turned on. When the actuation
lever 147 is moved forward along the sloped path, the latch switches 148
are turned off. The latch switches 148 are turned on or off by the
actuation lever 147 to start or end the operation of the microwave oven.
One end of the torsion spring 149 is fixed to the actuation lever 147,
and the other end of the torsion spring 149 is fixed to the latch board
146. Thus, the actuation lever 147 can be moved forward along the sloped
path by an elastic force of the torsion spring 149. That is, when the
latch protrusion 281 is drawn back from the latch slot 145, the actuation
lever 147 is automatically moved forward along the sloped path by the
torsion spring 149.

[0055]A smoke inlet portion 151 is formed in a bottom surface of the
cavity assembly 100. Smoke and fumes generated from food cooked on a
cooker disposed under the microwave oven are introduced into the cavity
assembly 100 through the smoke inlet portion 151 by operation of the vent
fan assembly 166. A filter (not shown) can be disposed on the smoke inlet
portion 151 for collecting particles and pollutant substances from the
smoke and fumes.

[0056]An electric component room 153 can be disposed at an upper lateral
portion of the cavity assembly 100 behind the inlet portion 121. In FIG.
1, the electric component room 153 is disposed at the upper right side of
the cavity assembly 100. The electric component room 153 contains various
electric components such as a magnetron 154 and a capacitor 155. Such
electric components disposed in the electric component room 153 are used
to generate microwaves for cooking foods. An opening 157 is formed in a
bottom surface of the electric component room 153. Air used to cool the
electric components of the electric component room 153 is guided to the
cooking chamber 111 through the opening 157.

[0057]A cooling fan assembly 159 is disposed in a front upper portion of
the cavity assembly 100 close to the inlet portion 121. The cooling fan
assembly 159 is used to generate airflows for cooling the door 200,
cooling the electric components of the electric component room 153, and
removing moisture, gaseous fatty substances, and odors generated from
food cooked in the cooking chamber 111. A suction portion of the cooling
fan assembly 159 is disposed close to the inlet portion 121, and a
discharge portion of the cooling fan assembly 159 is disposed toward the
electric component room 153. In FIG. 1, the discharge portion of the
cooling fan assembly 159 is disposed backward.

[0058]An air barrier 161 is disposed between a front upper portion of the
cavity assembly 100 and the electric component room 153. The air barrier
161 is a border structure between the electric components of the electric
component room 153 and the cooling fan assembly 159. An airflow generated
by operation of the cooling fan assembly 159 is guided to the electric
components of the electric component room 153 by the air barrier 161. As
shown in FIG. 5, the air barrier 161 can be formed of a metal and have a
rectangular shape having a predetermined length.

[0059]The air barrier 161 includes an air supply opening 162 to guide air
discharged from the discharge portion of the cooling fan assembly 159 to
the electric component room 153. The air barrier 161 further includes a
guide 163 to efficiently guide air from the air supply opening 162 to the
electric components of the electric component room 153, particularly, to
the magnetron 154 of the electric component room 153. In the current
embodiment, the guide 163 is formed by cutting a portion of the air
barrier 161 into a rectangular shape to form the air supply opening 162
and bending the cut portion toward the magnetron 154.

[0060]The air barrier 161 further includes a component mount portion 164
on one side. The component mount portion 164 is formed by bending a
portion of the air barrier 161 several times toward the front surface of
the cavity assembly 100. A component installation hole 165 is formed in
the component mount portion 164. The component installation hole 165 is
formed by cutting out a portion of the component mount portion 164
corresponding to the service opening 127 of the cavity assembly 100 into
a shape corresponding to a component (e.g., the capacitor 155 of the
electric component room 153) to be installed in the component
installation hole 165.

[0061]The vent fan assembly 166 is disposed in a rear side of a top
portion of the cavity assembly 100 behind the second outlet 124. Smoke
and fumes introduced into the cavity assembly 100 from food cooked on a
cooker disposed under the microwave oven are discharged forward from the
cavity assembly 100 by operation of the vent fan assembly 166. For this,
an inlet portion of the vent fan assembly 166 faces both sides of the
cavity assembly 100, and an outlet portion of the vent fan assembly 166
faces a front side of the cavity assembly 100 (i.e., the second outlet
124 of the cavity assembly 100).

[0062]First and second air guides 167 and 168 are disposed at the top
portion of the cavity assembly 100 between the second outlet 124 and the
vent fan assembly 166. Each of the second air guides 167 and 168 extends
at the top portion of the cavity assembly 100 in a front-to-back
direction to form a vent passage 169 for discharging smoke and fumes from
the cavity assembly 100 through the second outlet 124 when the vent fan
assembly 166 operates.

[0063]In FIG. 1, the first air guide 167 is disposed at the right of the
vent passage 169 between the electric component room 153 and the vent fan
assembly 166. Practically,

[0064]the first air guide 167 separates the electric component room 153
and the vent fan assembly 166. The first air guide 167 is L-shaped and
covers lateral and rear sides of the electric component room 153. The
first air guide 167 is sloped leftward toward the second outlet 124 so
that the cross sectional area of the vent passage 169 decreases as it
goes toward the second outlet 124. In other words, the vent passage 169
is narrowed by the electric component room 153.

[0065]A first air duct 171 is disposed at a side of the cavity assembly
100. Air introduced into the cavity assembly 100 by the cooling fan
assembly 159 to cool the electric components of the electric component
room 153 is guided to the cooking chamber 111 by the first air duct 171.
For this, the first air duct 171 is disposed at a right side of the
cavity assembly 100 under the electric component room 153 and is
connected to the inlet holes 113 and the opening 157.

[0066]A second air duct 172 is disposed at a side of the top portion of
the cavity assembly 100. Air circulating in the cooking chamber 111 is
guided to the first outlet 123 by the second air duct 172. The second air
duct 172 is disposed at a left side of the top portion of the cavity
assembly 100 above the cooking chamber 111 and communicates with the
outlet holes 115 and the first outlet 123.

[0067]A vent grill 173 is disposed at a front portion of the cavity
assembly 100 corresponding to the inlet portion 121 and the first and
second outlets 123 and 124. The vent grill 173 guides air to the inlet
portion 121 of the cavity assembly 100. Furthermore, the vent grill 173
guides air discharged through the first and second outlets 123 and 124.

[0068]As shown in FIG. 6, the vent grill 173 has a transversely elongated
polyhedral shape. The vent grill 173 includes a suction passage 174, a
first discharge passage 175, and a second discharge passage 176. The
suction passage 174 is formed in the vent grill, 173 and corresponds to
the inlet portion 121 of the cavity assembly 100. The first and second
discharge passages 175 and 176 are formed in the vent grill 173 and
correspond to the first and second outlets 123 and 124 of the cavity
assembly 100. That is, the suction passage 174 and the first discharge
passage 175 are formed in both sides of the vent grill 173, and the
second discharge passage 176 is formed in a center portion of the vent
grill 173 between the suction passage 174 and the first discharge passage
175. When the vent grill 173 is installed on the front portion of the
cavity assembly 100, the terminal housing is disposed in the first
discharge passage 175.

[0069]A pair of compartment ribs 177 is disposed in the vent grill 173 to
define the suction passage 174 and the first and second discharge
passages 175 and 176. That is, the suction passage 174 and the first and
second discharge passages 175 and 176 are defined by inner surfaces of
the vent grill 173 and both sides of the compartment ribs 177.

[0070]The suction passage 174 guides air to the inlet portion 121 of the
cavity assembly 100. The vent grill 173 includes first and second suction
grills 174A and 174B and a suction opening 174C. The first suction grill
174A is disposed on a top portion of the suction passage 174, and the
second suction grill 174B is disposed on a side portion of the suction
passage 174. The suction opening 174C is disposed on a rear portion of
the suction passage 174. The first suction grill 174A is disposed at a
right top side of the vent grill 173, and the second suction grill 174B
is disposed at a right lateral side of the vent grill 173 close to the
first suction grill 174A. The suction opening 174C is disposed at a right
rear side of the vent grill 173 close to the second suction grill 174B.
Air used to cool the door 200 or outside air is introduced into the
suction passage 174 through the first and second suction grills 174A and
174B. The suction opening 174C communicates with the inlet portion 121 of
the cavity assembly 100 such that air can flow from the suction passage
174 to the cavity assembly 100 through the suction opening 174C and the
inlet portion 121.

[0071]The second discharge passages 175 and 176 are configured to guide
air and fumes discharged from the cavity assembly 100 through the second
outlets 123 and 124. The front side of the vent grill 173 is sloped in an
upwardly extended shape such that air and fumes can be smoothly guided
upward from the cavity assembly 100 by the second discharge passages 175
and 176. The vent grill 173 includes a first discharge hole 175A at a top
surface of the first discharge passage 175, and a first discharge opening
175B at a rear surface of the first discharge passage 175. The first
discharge hole 175A is disposed at a left top surface of the vent grill
173, and the first discharge opening 175B is disposed at a left rear
surface of the vent grill 173 corresponding to the first discharge hole
175A. Air guided along the first discharge passage 175 is discharged
through the first discharge hole 175A. The first discharge opening 175B
communicates with the first outlet 123 of the cavity assembly 100 so that
air can flow from the cavity assembly 100 to the first discharge passage
175 through the first outlet 123 and the first discharge opening 175B.

[0072]The vent grill 173 further includes second discharge holes 176A at a
top surface of the second discharge passage 176, and second discharge
openings 176B at a rear surface of the second discharge passage 176. The
second discharge holes 176A are disposed at a top center portion of the
vent grill 173 between the second suction grill 174B and the first
discharge hole 175A. The second discharge openings 176B corresponding to
the second discharge holes 176A are disposed at a rear center portion of
the vent grill 173 between the first suction grill 174A and the first
discharge opening 175B. Smoke and fumes, which are discharged from the
cavity assembly 100 and guided along the second discharge passage 176,
are discharged through the second discharge holes 176A. In the current
embodiment, a pair of second discharge holes 176A is provided. The second
discharge openings 176B communicate with the second outlet 124 such that
smoke and fumes discharged from the cavity assembly 100 can be guided to
the second discharge passage 176 through the second outlet 124 and the
second discharge openings 176B.

[0073]A pair of fixing ribs 178 is disposed on a rear edge portion of the
top surface of the vent grill 173. The fixing ribs 178 protrude backward
from the rear edge portion of the vent grill 173 by a predetermined
length. The fixing ribs 178 include penetration holes 178A. When
attaching the vent grill 173 to the cavity assembly 100, screws are fixed
to the front side of the cavity assembly 100 through the penetration
holes 178A.

[0074]A lead wire opening 179 is formed in a left side of the vent grill
173 close to the first discharge passage 175. Referring to FIG. 7, a lead
wire (W) is connected to the door 200 through the lead wire opening 179
to connect the display unit 260 of the door 200 to the terminal coupled
to the terminal housing. The lead wire opening 179 can be formed to a
predetermined depth by cutting out a left portion of the vent grill 173.

[0075]A lead wire cap 181 is detachably attached to the first discharge
passage 175. The lead wire cap 181 separates the lead wire (W) from a
portion of the first discharge passage 175 where air discharged from the
cavity assembly 100 flows. In detail, air discharged from the cavity
assembly 100 to the first discharge passage 175 flows in the lead wire
cap 181, and the lead wire (W) is disposed in a wire accommodation gap
182 defined between the first discharge passage 175 and the lead wire cap
181.

[0076]The lead wire cap 181 has a polyhedral shape with opened top and
rear sides. When the lead wire cap 181 is attached to the first discharge
passage 175, front and lateral surfaces of the lead wire cap 181 are
spaced a predetermined distance from front and lateral surfaces of the
first discharge passage 175 (i.e., from inner surfaces of the vent grill
173 and the compartment ribs 177). The lead wire cap 181 can be
detachably attached to the first discharge passage 175 by inserting the
lead wire cap 181 into the first discharge passage 175 through the first
discharge hole 175A. The lead wire cap 181 includes fixing tabs 183 and a
rib grip 184 at a front upper portion. The fixing tabs 183 protrude
forward from the front upper portion of the lead wire cap 181, and the
rib grip 184 extends upward from the front upper portion of the lead wire
cap 181. When the lead wire cap 181 is inserted into the first discharge
passage 175, the fixing tabs 183 are hooked by a top portion of the vent
grill 173 at the first discharge hole 175A so that the lead wire cap 181
can be securely held in the first discharge passage 175. The lead wire
cap 181 can be detached from the first discharge passage 175 after moving
the fixing tabs 183 away from the top portion of the vent grill 173 using
the rib grip 184.

[0077]The door 200 for opening and closing the cooking chamber 111 is
rotatably attached to the cavity assembly 100 in a manner such that the
door 200 can be rotated up and down on its upper edge portion. Referring
to FIG. 8, the door 200 includes a door panel 210, a doorframe 220, a
choke cover 230, a front member such as a front cover 240 and a front
glass 250, the display unit 260, and a door handle 270.

[0078]The door panel 210 has a rectangular shape and is a base structure
of the door 200. The door panel 210 includes a see-through opening 211. A
user can see the inside cooking chamber 111 through the see-through
opening 211 without having to open the door 200. The see-through opening
211 can be formed by cutting a center portion of the door panel 210 into
a rectangular shape.

[0079]A display opening 213 is formed in the door panel 210 under the
see-through opening 211. The display unit 260 is exposed through the
display opening 213. The display opening 213 can be formed by cutting a
portion of the door panel 210 located under the see-through opening 211
into a rectangular shape.

[0080]An interference preventing portion 215 is formed on a top end of the
door panel 210. The interference preventing portion 215 is formed to
prevent interference between the door 200 and the vent grill 173 when the
door 200 is rotated up or down on its upper edge portion to open or close
the cooking chamber 111. The interference preventing portion 215 can be
formed by cutting a top end portion of the door panel 210 into a shape
corresponding to the vent grill 173.

[0081]Inlet holes 217 and outlet holes 219 are formed in the topside of
the door panel 210. The inlet holes 217 allow inflow of outside air to a
door cooling passage 201 (refer to FIG. 9). The outlet holes 219 allows
outflow of air from the door cooling passage 201. The inlet holes 217 are
disposed at one side of the topside of the door panel 210 such that the
inlet holes 217 is close to the first discharge hole 175A of the vent
grill 173 when the door 200 is attached to the cavity assembly 100. The
outlet holes 219 are disposed at a side of the interference preventing
portion 215 away from the inlet holes 217. That is, the outlet holes 219
are disposed at the other side of the topside of the door panel 210 away
from the inlet holes 217.

[0082]The doorframe 220 is disposed at a rear side of the door panel 210.
A plurality of chokes 221 disposed on edge portions of the doorframe 220.
The chokes 221 prevent leakage of microwaves from the cooking chamber
111. An opening portion 223 corresponding to the see-through opening 211
of the door panel 210 is formed in a center portion of the doorframe 220.

[0083]An interference preventing portion 225 is formed on a top end of the
doorframe 220. The interference preventing portion 225 can be formed by
cutting a top end portion of the doorframe 220 into a shape corresponding
to the interference preventing portion 215 (i.e., corresponding to the
vent grill 173).

[0084]A pair of hinge flanges 227 is disposed at each lateral side of the
doorframe 220. The hinge flanges 227 are spaced a predetermined distance
from the lateral side of the 220. The hinge pin 228 is horizontally
disposed between the hinge flanges 227. Practically, the door 200 rotates
on the hinge pin 228. When the door 200 is attached to the cavity
assembly 100, the hinge pin 228 is inserted in the hinge grooves 134 and
the hinge pin openings 138 of the door support bracket 131.

[0085]Spring fixing pins 229 are disposed on both sides of the doorframe
220 under the hinge flanges 227. The spring fixing pins 229 are used to
fix the gas springs 300 (refer to FIG. 300). When assembled, the spring
fixing pins 229 are inserted into side portions of spring accommodation
portions 235 (described later) and disposed in the spring accommodation
portions 235.

[0086]The choke cover 230 is disposed at a rear side of the doorframe 220.
The choke cover 230 is disposed at an opposite side to the door panel 210
with respect to the doorframe 220. The choke cover 230 forms a rear outer
surface of the door 200. The choke cover 230 includes a see-through
opening 231 corresponding to the see-through opening 211 of the door
panel 210 and the opening portion 223 of the doorframe 220. The
see-through opening 231 can be formed by cutting out a center portion of
the choke cover 230 into a rectangular shape.

[0087]An interference preventing portion 233 is formed on a top end of the
choke cover 230. Like the interference preventing portion 215 of the door
panel 210 and the interference preventing portion 225 of the doorframe
220, the interference preventing portion 233 can be formed by cutting a
top end portion of the choke cover 230 into a shape corresponding to the
vent grill 173.

[0088]The spring accommodation portions 235 are disposed on both sides of
the choke cover 230. When the door 200 closes the cooking chamber 111,
the gas springs 300 is disposed in the spring accommodation portions 235.
Each of the spring accommodation portions 235 has a vertically elongated
hexahedron shape. The spring accommodation portions 235 can be formed by
recessing side portions of the choke cover 230 toward the doorframe 220.

[0089]Latch holes 237 corresponding to the latch slots 145 of the cavity
assembly 100 are formed in both sides of the choke cover 230. When
assembled, the latch protrusions 281 are inserted into the latch holes
237 and protruded backward. The latch holes 237 can be formed by cutting
out side portions of the choke cover 230 into a shape corresponding to
the latch protrusions 281. The latch holes 237 have a predetermined width
corresponding to the width of the latch protrusions 281.

[0090]The front cover 240 is disposed at a front side of the door panel
210. Practically, the front cover 240 forms the front exterior of the
door 200. The front cover 240 can be formed of a metal. In the current
embodiment, the front cover 240 is approximately U-shaped with an opened
top to enclose the see-through opening 211 and the display opening 213 of
the door panel 210.

[0091]The front glass 250 forms the front exterior of the door 200
together with the front cover 240. For this, the front glass 250 is
disposed at a position corresponding to the see-through opening 211 and
the interference preventing portion 215 of the door panel 210. That is,
the front glass 250 covers the see-through opening 211 and the
interference preventing portion 215 of the door panel 210.

[0092]The display unit 260 is used to receive various operational commands
and display various information about operation of the microwave oven.
The display unit 260 is surrounded by the door cooling passage 201. The
display unit 260 includes a main printed circuit board substrate 261, a
backlight printed circuit board substrate 263, a reflector 265, a display
cover 267, and a display glass 269.

[0093]When assembled, the main printed circuit board substrate 261 is
disposed in a portion of the door 200 corresponding to the display
opening 213 of the door panel 210. That is, the main printed circuit
board substrate 261 is disposed between the door panel 210 and the
doorframe 220. A display device 262 is disposed on a front surface of the
main printed circuit board substrate 261. The display device 262 is
exposed through the display opening 213 of the door panel 210 and
displays various information about operation of the microwave oven. A
vacuum fluorescent display (VFD), which uses radiation of a fluorescent
material caused by a low-speed electron ray, can be used as the display
device 262. The display device 262 is fixed to the main printed circuit
board substrate 261 using a fixing bracket 262A. The main printed circuit
board substrate 261 includes a plurality of electric components (not
shown) for operation of the display unit 260. The lead wire (W) (refer to
FIG. 9) is connected to the main printed circuit board substrate 261
through the lead wire opening 179 of the vent grill 173.

[0094]The backlight printed circuit board substrate 263 is disposed in the
door 200 at a front side of the main printed circuit board substrate 261.
That is, the backlight printed circuit board substrate 263 is disposed
between the door panel 210 and the main printed circuit board substrate
261. A plurality of light emitting diodes (not shown) is disposed on a
front side of the backlight printed circuit board substrate 263. The
light emitting diodes emit light to illuminate buttons 266 (described
later). The backlight printed circuit board substrate 263 includes a
display opening for receiving the display device 262.

[0095]The reflector 265 is disposed in the door 200 between the door panel
210 and the backlight printed circuit board substrate 263. The reflector
265 reflects light emitted from the light emitting diodes of the
backlight printed circuit board substrate 263. The buttons 266 are
disposed on a front side of the reflector 265 that is exposed through the
display opening 213 of the door panel 210. The buttons 266 can be
touch-screen buttons for receiving operational commands. Like the
backlight printed circuit board substrate 263, the reflector 265 includes
a display opening.

[0096]The display cover 267 disposed at a front side of the reflector 265.
Characters or symbols are printed on the display cover 267 for indicating
functions of the buttons 266. A film coated with a conductive indium tin
oxide (ITO) compound can be used as the display cover 267 to allow the
buttons 266 to operate as touch-screen buttons for receiving operational
commands. Like the backlight printed circuit board substrate 263 and the
reflector 265, the display cover 267 includes a display opening.

[0097]The display glass 269 is disposed at a front side of the display
cover 267 and forms a portion of the front exterior of the door 200. For
this, the display glass 269 has a rectangular shape corresponding to the
shape of the display opening 213 of the door panel 210 and is disposed on
the display opening 213 of the door panel 210.

[0098]The display unit 260 is assembled as a single module and is fixed to
the rear surface of the door panel 210. In other words, the main printed
circuit board substrate 261, the backlight printed circuit board
substrate 263, the reflector 265, the display cover 267, and the display
glass 269 are assembled into the display unit 260 independently of other
components of the door 200, and then the display unit 260 is fixed to the
rear surface of the door panel 210.

[0099]The door handle 270 is used when a user rotates the door 200. The
door handle 270 can have a hollow rod shape and be transversely disposed
on the front cover 240. Both ends of the door handle 270 are fixed to the
door panel 210 through the front cover 240.

[0100]The pair of latch protrusions 281 is disposed between the door panel
210 and the choke cover 230. The latch protrusions 281 are inserted into
the latch holes 237 and protrude backward from the door 200. When the
door 200 is rotated down to close the cooking chamber 111, the latch
protrusions 281 lock the door 200 in the closed position. The latch
protrusions 281 are horizontally arranged. Each of the latch protrusions
281 includes a latch hole for selectively receiving the actuation lever
147 of the latch board 146.

[0101]The door cooling passage 201 is formed in the door 200. The door
cooling passage 201 is formed to cool the door 200, particularly, the
display unit 260. Substantially, the door cooling passage 201 is formed
by the door panel 210 and the choke cover 230. The door cooling passage
201 is formed in the door 200 into an approximate U-shape with opened
tops. The opened tops of the door cooling passage 201 are connected to
the inlet holes 217 and the outlet holes 219 of the door panel 210.

[0102]A handle cooling passage 271 (refer to FIG. 9) is formed in the door
handle 270. The handle cooling passage 271 is formed to cool the door
handle 270. Both ends of the handle cooling passage 271 are connected to
the door cooling passage 201. Thus, some air flows from the door cooling
passage 201 to the handle cooling passage 271.

[0103]The pair of gas springs 300 support the door 200 with respect to the
cavity assembly 100 when the cooking chamber 111 is opened. When the door
200 is at a position between fully closed and opened positions, the gas
springs 300 apply a torque to the door 200 for closing or further opening
the cooking chamber 111 based on a reference position between the fully
closed and opened positions of the door 200. For example, the reference
position can be a middle position between the fully closed and opened
positions of the door 200 (refer to FIG. 15). In this case, when the door
200 is at a position above the reference position, the gas springs 300
apply a torque to the door 200 to rotate the door 200 up to the fully
opened position. When the door is at a position below the reference
position, the gas springs 300 apply a torque to the door 200 to rotate
the door 200 down to the fully closed position.

[0104]Referring to FIG. 1, each of the gas springs 300 includes a cylinder
310 in which gas is filled, and a piston rod 320 inserted into the
cylinder 310. The piston rod 320 is linearly movable by pressure of the
gas filled in the cylinder 310. One end of the piston rod 320 is inserted
into one end of the cylinder 310. The other end of the piston rod 320 is
rotatably supported on the rear surface of the door panel 210, and the
other end of the cylinder 310 is rotatably supported on the front surface
of the cavity assembly 100. In detail, the other end of the cylinder 310
is rotatably supported on the fixing protrusion 143 of the cavity
assembly 100, and the other end of the piston rod 320 is rotatably
supported on the spring fixing pin 229 of the door panel 210.

[0105]When the door 200 is closed (i.e., when the cooking chamber 111 is
closed), the gas springs 300 are disposed in the spring accommodation
portions 235 of the door 200. When the door 200 is fully rotated down to
close the cooking chamber 111, the front surface of the cavity assembly
100 and the rear surface of the door 200 are not spaced apart from each
other owing to the gas springs 300.

[0106]An exemplary operation of the ventilation hooded microwave oven will
now be described in detail with reference to the accompanying drawings
according to the first embodiment.

[0107]First, procedures for installing the door 200 to the cavity assembly
100 will now be described according to the first embodiment.

[0108]FIGS. 10 to 12 are partial perspective views for explaining
procedures for installing the door 200 to the cavity assembly 100
according to the first embodiment.

[0109]For example, the cavity assembly 100 is installed in furniture (not
shown) above a cooker (not shown). In this state, as shown in FIG. 10,
the door 200 is moved toward the cavity assembly 100 in a manner such
that the hinge pin 228 can be moved down into the hinge grooves 134.
Here, the coupling hole 136 of the hinge bracket 133 is exposed to the
outside of the furniture.

[0110]Thereafter, as shown in FIG. 11, the hinge cover 137 is rotated down
to securely hold the hinge pin 228 in the hinge grooves 134. Here, when
the hinge cover 137 is rotated down, the hinge pin 228 is inserted into
the hinge pin openings 138 from bottoms to tops of the hinge pin openings
138. Then, the penetration hole 139 of the hinge cover 137 is vertically
aligned with the coupling hole 136 of the hinge bracket 133.

[0111]In this way, detachment of the hinge pin 228 can be prevented using
the hinge cover 137. Thereafter, as shown in FIG. 12, a screw (S) is
fixed to the coupling hole 136 of the hinge bracket 133 through the
penetration hole 139 of the hinge cover 137. By this, the hinge cover 137
can be securely fixed, and thus detachment of the hinge pin 228 can be
reliably prevented.

[0112]As explained above, the coupling hole 136 of the hinge bracket 133,
and the penetration hole 139 of the hinge cover 137 are exposed to the
outside of the furniture. Therefore, the door 200 can be attached to the
cavity assembly 100 without having to separate the cavity assembly 100
from the furniture.

[0113]Next, it will be described how the door 200 of the ventilation
hooded microwave oven is opened according to the first embodiment.

[0114]FIGS. 13 to 17 are views for explaining how the door 200 of the
ventilation hooded microwave oven is opened according to the first
embodiment.

[0115]Referring to FIG. 13, when the door 200 is closed (i.e., when the
cooking chamber 111 is closed), the rear surface of the door 200 is in
contact with the front surface of the cavity assembly 100. In this state,
the latch protrusion 281 is in the latch slot 145, and the actuation
lever 147 is accommodated in the latch protrusion 281. Thus, the latch
protrusion 281 is not freely released from the latch slot 145.

[0116]Meanwhile, when the latch protrusion 281 is inserted into the latch
slot 145, the actuation lever 147 is pushed by the latch protrusion 281
so that the latch switches 148 can be turned on. Then, an operational
command can be input using the buttons 266 of the display unit 260 to
operate the microwave oven according to the input operational command for
cooking food in the cooking chamber 111.

[0117]After the food is cooked in the cooking chamber 111, the cooking
chamber 111 can be opened by rotating up the door 200. For example, a
user can pull the door handle 270 in an upwardly curved direction to
rotate up a lower end of the door 200 about the hinge pins 228 so as to
open the cooking chamber 111 as shown in FIG. 14. At this time, the latch
protrusions 281 are released from the latch slots 145. After the latch
protrusions 281 are released from the latch slots 145, the actuation
lever 147 moves back to its initial position by a force applied to the
actuation lever 147 from the torsion springs 149.

[0118]Until the door 200 is rotated up to a predetermined position (e.g.,
the middle position between fully closed and opened positions), the gas
springs 300 apply a reverse torque to the door 200 to rotate down the
door 200 back to the fully closed position. Thus, unless the user pulls
the door handle 270 in an upwardly curved direction to the predetermined
position, the lower end of the door 200 may rotate down about the hinge
pins 228 to the closed position to close the cooking chamber 111.

[0119]However, if the user pulls the door handle 270 above the
predetermined position, the lower end of the door 200 can be rotated
upward about the hinge pins 228 to the fully closed position. Referring
to FIG. 15, the door 200 is positioned above the middle position between
fully closed and opened positions. In this state, the gas springs 300
apply a torque to the door 200 to rotate the lower end of the door 200
upward about the hinge pins 228 so as to fully open the cooking chamber
111.

[0120]Therefore, as shown in FIG. 16, although the user does not pull the
door handle 270 after the door 200 is positioned above the middle
position, the door 200 can be rotated upward to open the cooking chamber
111. Referring to FIG. 17, the door 200 is rotated upward to the fully
opened position. That is, the cooking chamber 111 is fully opened.

[0121]After the cooking chamber 111 is opened in this way, cooked food can
be taken out of the cooking chamber 111, or non-cooked food can be placed
into the cooking chamber 111. Here, since the gas springs 300 apply a
torque to the opened door 200 in an upward direction, the door 200 is not
freely moved from the opened position so that loading and unloading of
food into and from the cooking chamber 111 can be conveniently carried
out without interruption by the door 200.

[0122]After loading food into the cooking chamber 111 or unloading food
from the cooking chamber 111, the user can close the cooking chamber 111
by pushing the door 200 downwardly to the closed position. The closing of
the cooking chamber 111 can be carried out in a reverse order as compared
with the opening of the cooking chamber 111. That is, when a user pushes
the door handle 270 forward and downward, the door 200 starts to rotate
down about the hinge pins 228. After the door 200 is rotated down below
the middle position between the fully closed and opened position (refer
to FIG. 15), the gas springs 300 apply a torque to the door 200 to rotate
down the lower end of the door 200 about the upper end of the door 200.
Therefore, although the user does not push the door handle 270 after the
door 200 is positioned below the middle position, the lower end of the
door 200 can be rotated down about the upper end of the door 200 to close
the cooking chamber 111.

[0123]Next, exemplary airflows in the ventilation hooded microwave oven
will be described according to the first embodiment.

[0124]FIGS. 18 to 20 are views illustrating exemplary airflows in the
ventilation hooded microwave oven according to the first embodiment.

[0125]When the microwave oven start to operate, the cooling fan assembly
159 sucks air into the door cooling passage 201 through the inlet holes
217 of the door 200 as shown in FIG. 18. While flowing along the door
cooling passage 201, the air cools the door 200, particularly, the
display unit 260.

[0126]Some of the air flows from the door cooling passage 201 to the
handle cooling passage 271 to cool the door handle 270. Thereafter, the
air flows back to the door cooling passage 201. After the air is used to
cools the door 200 and the door handle 270, the air is discharged from
the door cooling passage 201 through the outlet holes 219 of the door
200.

[0127]Referring to FIG. 19, the air discharged from the door cooling
passage 201 through the outlet holes 219 is introduced into the suction
passage 174 of the vent grill 173 through the first suction grill 174A.
Then, the air flows from the suction passage 174 to the cavity assembly
100 through the suction opening 174C of the vent grill 173 and the inlet
portion 121 of the cavity assembly 100. As well as the air used to cool
the door 200 and introduced into the cavity assembly 100 through first
suction grill 174A, other outside air can be introduced into the cavity
assembly 100 through the second suction grill 174B of the vent grill 173.

[0128]The air introduced into the cavity assembly 100 is directed to the
electric component room 153 through the air supply opening 162 of the air
bather 161 to cool electric components such as the magnetron 154 and the
capacitor 155. Here, the guide 163 of the air barrier 161 guides the air
to the electric components. Thereafter, the air is guided to the first
air duct 171 through the opening 157.

[0129]The air guided to the first air duct 171 flows into the cooking
chamber 111 through the inlet holes 113 of the cooking chamber 111 as
shown in FIG. 20. Then, the air flows from the cooking chamber 111 to the
second air duct 172 through the outlet holes 115. Here, while passing
through the cooking chamber 111, the air absorbs moisture, gaseous fatty
substances, and odors generated from food cooked in the cooking chamber
111. The air containing such substances is guided from the second air
duct 172 to the first discharge passage 175 of the vent grill 173 through
the first outlet 123 of the cavity assembly 100. Then, the air is
discharged from the first discharge passage 175 through the first
discharge hole 175A. Here, the air discharged from the cavity assembly
100 to the first discharge passage 175 is guided upward through the first
discharge hole 175A.

[0130]Meanwhile, as shown in FIG. 19, when the vent fan assembly 166
operates, smoke and fumes generated from food cooked on a cooker disposed
under the microwave is introduced into the cavity assembly 100 through
the smoke inlet portion 151 (refer to FIG. 1). Then, the smoke and fumes
flow along the vent passage 169 and are guided to the second discharge
passage 176 of the vent grill 173 through the second outlet 124 of the
cavity assembly 100. The smoke and fumes are discharged upward from the
second discharge passage 176 through the second discharge holes 176A of
the vent grill 173.

[0131]When the capacitor 155 is damaged or broken, the capacitor 155 can
be replaced with a new one without having to separate the cavity assembly
100 from the furniture. In detail, the service opening 127 (i.e., the
opening/closing bracket 129) can be exposed by rotating the door 200
upward on the hinge pins 228 to open the cooking chamber 111. Thereafter,
the opening/closing bracket 129 can be separated from the cavity assembly
100 to open the service opening 127. Then, the capacitor 155 installed in
the component installation hole 165 of the air barrier 161 can be
detached through the service opening 127, and a new capacitor 155 can be
installed in the component installation hole 165. After replacing the
capacitor 155, the opening/closing bracket 129 is attached to the front
of the cavity assembly 100 to close the service opening 127. In this way,
replacing of the capacitor 155 can be completed.

[0132]Although embodiments have been described with reference to a number
of illustrative embodiments thereof, it should be understood that
numerous other modifications and embodiments can be devised by those
skilled in the art that will fall within the scope of the disclosure, the
drawings and the appended claims.

[0133]For example, although the spring accommodation portions are formed
in the rear surface of the door in the above-described embodiment, the
spring accommodation portions can be formed in the front surface of the
cavity assembly in other embodiments. Furthermore, a damping member can
be disposed at a lower portion of the front surface of the cavity
assembly or a lower portion of the rear surface of the door in order to
reduce shocks and noises when the door is rotated to close or open the
cooking chamber of the cavity assembly.

Mode for the Invention

[0134]A ventilation hooded microwave oven will now be described in detail
with reference to the accompanying drawings according to other
embodiments.

[0135]FIG. 21 is a side view illustrating a door support device of a
ventilation hooded microwave oven according to a second embodiment, and
FIG. 22 is a partial perspective view illustrating a door support device
of a ventilation hooded microwave oven according to a third embodiment.

[0136]In the embodiment shown in FIG. 21, hinge brackets 410 (one shown in
FIG. 21) are disposed at both sides of a front upper portion of a cavity
assembly (not shown) to support a door (not shown) with respect to the
cavity assembly in a manner such that a lower end of the door can be
rotated upward and downward about an upper end of the door. A hinge
groove 420 is formed in a leading end of the hinge bracket 410. The hinge
groove 420 is opened backwardly. Thus, the leading end of the hinge
bracket 410 can be U-shaped.

[0137]Opening/closing members 430 (one shown in FIG. 21) are disposed at
both sides of an upper end portion of the cavity assembly close to the
hinge brackets 410. The opening/closing members 430 are vertically
movable. The opening/closing member 430 selectively opens and closes the
hinge groove 420. For this, the opening/closing member 430 has a side
portion making contact with the hinge bracket 410 and is vertical movable
to close and open the hinge groove 420 selectively. The opening/closing
member 430 disposed at the upper end portion of the cavity assembly does
not overlap the hinge groove 420.

[0138]Elastic members (not shown) are disposed at both sides of the upper
end portion of the cavity assembly to apply an elastic force to the
opening/closing members 430 to move the opening/closing members 430
upwardly. For example, coil springs can be vertically disposed as the
elastic members. After the opening/closing member 430 is moved up to
close the hinge groove 420, the opening/closing member 430 is not freely
moved down owing to the elastic member, and thus the closed state of the
hinge groove 420 can be reliably maintained.

[0139]A pair of hinge flanges 440 is disposed at each lateral side of an
upper rear portion of the door. The hinge flanges 440 are spaced a
predetermined distance from the lateral side of the upper rear portion of
the door. The predetermined distance is at least greater than the sum of
the thicknesses of the hinge bracket 410 and the opening/closing member
430.

[0140]The hinge flanges 440 protrude backward from the lateral side of the
upper rear portion of the door, and a hinge pin 450 is horizontally
disposed between the hinge flanges 440. The hinge pin 450 is disposed in
the hinge groove 420 by inserting the hinge pin 450 into the hinge groove
420 from the back of the hinge groove 420. Practically, the hinge pin 450
is a rotation center of the door rotatably attached to the cavity
assembly.

[0141]In the current embodiment, the door can be rotatably attached to the
cavity assembly as follows. First, the door is moved toward the cavity
assembly to place the hinge pin 450 above the opening/closing member 430.
Next, the door is moved down to push the opening/closing member 430 with,
the hinge pin 450.

[0142]Then, the opening/closing member 430 is moved down by the hinge pin
450, and the hinge pin 450 makes contact with the hinge bracket 410. In
this state, the door is moved forward to insert the hinge pin 450 into
the hinge groove 420. When the hinge pin 450 is inserted into the hinge
groove 420, the hinge pin 450 departs from the opening/closing member 430
such that the opening/closing member 430 can be lifted by the resilience
of the elastic member to close the hinge groove 420. Since the
opening/closing member 430 closes the hinge groove 420, the hinge pin 450
inserted into the hinge groove 420 is not freely released from the hinge
groove 420.

[0143]In the embodiment shown in FIG. 22, hinge brackets 510 are disposed
at both sides of a front upper portion of a cavity assembly (not shown).
The hinge brackets 510 protrude forward from both sides of the front
upper portion of the cavity assembly. Each of the hinge brackets 510
includes a hinge hole (not shown).

[0144]A door (not shown) is attached to the cavity assembly in a manner
such that a lower end of the door can be rotatable about an upper end of
the door. A pair of hinge flanges 520 is disposed at each lateral side of
a rear upper portion of the door. The hinge flanges 520 are spaced a
predetermined distance from the lateral side of the rear upper portion of
the door. The hinge flanges 520 protrude backward from the rear upper
portion of the door.

[0145]A hinge pin 530 is disposed on one of the hinge flanges 520. The
hinge pin 530 protrudes horizontally from one of the hinge flanges 520
toward the other of the hinge flanges 520. A leading end of the hinge pin
530 is spaced a predetermined distance from the other of the hinge
flanges 520. When assembled, the hinge pin 530 is horizontally inserted
in the hinge hole of the hinge bracket 510.

[0146]After inserting the hinge pin 530 into the hinge hole of the hinge
bracket 510, a closing member 540 is inserted between the leading end of
the hinge pin 530 and the other of the hinge flange 520. The closing
member 540 prevents the hinge pin 530 from freely departing from the
hinge hole of the hinge bracket 510.

[0147]A ventilation hooded microwave oven will now be described in detail
with reference to the accompanying drawings according to a fourth
embodiment.

[0148]FIG. 23 is a perspective view illustrating a cam hinge of a
ventilation hooded microwave oven according to a fourth embodiment.

[0149]In the current embodiment, a cooking chamber (not shown) disposed in
a cavity assembly (not shown) is closed and opened using a door (not
shown), and a pair of cam hinges 600 (one shown in FIG. 23) is used to
attach the door to the cavity assembly in a manner such that a lower end
of the door can be rotated about an upper end of the door.

[0150]The cam hinges 600 apply a torque to the door in a direction for
opening the door or closing the door according to the angular position of
the door. In other words, the cam hinges 600 apply a torque to the door
in different directions based on a reference angular position of the
door. For example, when the door is positioned above the reference
regular position, the cam hinges 600 apply a torque to the door in a
predetermined direction to rotate up the lower end of the door about the
upper end of the door so as to open the cooking chamber. When the door is
positioned below the reference regular position, the cam hinges 600 apply
a torque to the door in an opposite direction to rotate down the door for
closing the cooking chamber.

[0151]For this, each of the cam hinges 600 includes a long cam housing
610, a hinge protrusion 620, a rotation cam 630, a movable cam 640, and
an elastic member 650. One end portion of the hinge protrusion 620 is
inserted in an end of the cam housing 610, and the other end portion of
the hinge protrusion 620 protrudes from the end of the cam housing 610.
The rotation cam 630 is disposed in the cam housing 610 and is rotatable
on the hinge protrusion 620. The movable cam 640 is disposed in the cam
housing 610 and is movable in a length direction of the cam housing 610.
The elastic member 650 elastically supports the movable cam 640. The
hinge protrusions 620 of the cam hinges 600 are oriented such that the
hinge protrusions 620 protrude from the cam hinges 600 in opposite
directions.

[0152]The cam housing 610 forms the exterior of the cam hinge 600. The cam
housing 610 has a hollow cylindrical shape having a predetermined length.
A hinge hole 611 is formed on the end of the cam housing 610 to receive
the hinge protrusion 620.

[0153]The hinge protrusion 620 is inserted in the hinge hole 611. A
portion of the hinge protrusion 620 protrudes outward from the cam
housing 610, and the other portion of the hinge protrusion 620 is
disposed in the cam housing 610. When assembled, the portion of the hinge
protrusion 620 protruding from the cam housing 610 is inserted in a hinge
hole (not shown) of the cavity assembly and functions as a rotation
center of the door. When the door attached to the cavity assembly
rotates, the hinge protrusion 620 rotates relative to the cam housing
610.

[0154]The rotation cam 630 is disposed at the other portion of the hinge
protrusion 620 disposed in the cam housing 610. When the hinge protrusion
620 rotates upon the rotation of the door, the rotation cam 630 also
rotates together with the hinge protrusion 620. The rotation cam 630
includes a cam groove 631 on a side opposite to the hinge protrusion 620.
The cam groove 631 can be formed by recessing a portion of the rotation
cam 630 into a predetermined shape.

[0155]The movable cam 640 is moved in a length direction of the cam
housing 610 by the rotation of the rotation cam 630. A cam protrusion 641
is formed on a side of the movable cam 640 facing the rotation cam 630.
That is, the cam protrusion 641 faces the cam groove 631. The cam
protrusion 641 can be formed by protruding a portion of the movable cam
640 into a shape corresponding to the shape of the cam groove 631.

[0156]The elastic member 650 applies an elastic force to the movable cam
640 to push the movable cam 640 against the rotation cam 630. The elastic
member 650 is longitudinally disposed in the cam housing 610. A coil
spring can be used as the elastic member 650. In this case, one end of
the coil spring may be supported on an end of the cam housing 610
opposite to the hinge protrusion 620, and the other end of the coil
spring may be supported on the movable cam 640.

[0157]An exemplary operation of the ventilation hooded microwave oven will
now be described in detail with reference to the accompanying drawings
according to the fourth embodiment.

[0158]FIGS. 24 and 25 are perspective views illustrating how the cam hinge
600 operates when the door of the ventilation hooded microwave oven is
opened and closed according to the fourth embodiment.

[0159]When the cooking chamber of the cavity assembly is closed by the
door (i.e., when the door does not rotate relative to the cavity
assembly), the cam protrusion 641 is in the cam groove 631, and the
rotation cam 630 and the movable cam 640 are fully in contact with each
other as shown in FIG. 23. Therefore, the rotation cam 630 does not
freely rotate so that the door can be reliably held in the closed
position, and the closed state of the cooking chamber can be reliably
maintained.

[0160]When a user pulls the door in an upwardly sloped direction, the
lower end of the door is rotated upward about the hinge protrusion 620.
Therefore, as shown in FIG. 24, the hinge protrusion 620 is rotated
clockwise, and thus the cam protrusion 641 of the movable cam 640 departs
from the cam groove 631 of the rotation cam 630.

[0161]The elastic member 650 pushes the movable cam 640 toward the
rotation cam 630. Therefore, if the user stops pulling of the door before
the cam protrusion 641 fully departs from the cam groove 631 (i.e.,
before the door rotates about the hinge protrusion 620 by more than a
predetermined angle), the cam protrusion 641 of the movable cam 640 is
moved back into the cam groove 631 of the rotation cam 630 by the elastic
member 650. That is, the lower end of the door rotates down about the
hinge protrusion 620, and thus the cooking chamber is closed again.

[0162]However, if the user does not stop pulling of the door until the
door rotates about the hinge protrusion 620 by more than the
predetermined angle, the cam protrusion 641 fully departs from the cam
groove 631, and thus the top surface of the cam protrusion 641 makes
contact with the bottom surface of the rotation cam 630. Therefore,
although the elastic member 650 pushes the movable cam 640 toward the
rotation cam 630, the rotation cam 630 is not rotated owing to, for
example, a frictional force between the top surface of the cam protrusion
641 and the bottom surface of the rotation cam 630. That is, the door
does not freely rotate down about the hinge protrusion 620 to close the
cooking chamber.

INDUSTRIAL APPLICABILITY

[0163]According to the present disclosure, the ventilation hooded
microwave oven and the cooling system for the ventilation hooded
microwave oven have good industrial applicability owing to the following
advantages.

[0164]In the present disclosure, the cooking chamber can be opened and
closed by rotating up or down the lower end portion of the door about the
upper end portion of the door. Therefore, after rotating up the door to
open the cooking chamber, left and right outer spaces of the ventilation
hooded microwave oven can be freely used, thereby increasing efficiency
in utilization of the space of a kitchen where the ventilation hooded
microwave oven is placed.

[0165]Furthermore, owing to the interference preventing portion formed on
an upper portion of the door into a shape corresponding to the shape of
the vent grill used to guide air discharged from the cavity assembly of
the microwave oven, interference between the door and the vent grill can
be prevented when the door is rotated up or down to open or close the
cooking chamber of the microwave oven.

[0166]Furthermore, electric components of the electric component room can
be repaired or replaced through the service opening formed in a front
side of the cavity assembly. Therefore, rapid repair and simple
maintenance of the ventilation hooded microwave oven can be possible.

[0167]Furthermore, the size of the vent passage can be practically reduced
owing to the air guides, and the saved space can be used for the electric
component room. That is, although the size of the vent passage is reduced
to allocate sufficiently large space for the electric component room, air
can be smoothly discharged from the cavity assembly through the vent
passage.

[0168]In addition, components of the cavity assembly are connected to the
display unit installed in the door by laying the lead wire between the
components and the display unit through a gap between the vent grill and
the lead wire cap. Therefore, the lead wire can be reliably protected,
and thus the ventilation hooded microwave oven can operate reliably.

[0169]Moreover, the door and the door handle are cooled by flowing air
therethrough. Therefore, accidents resulting from extreme temperature of
the door and the door handle can be prevented, and the display unit
disposed at the door can be prevented from being damaged by heat.